Of optical glasses for producing optical elements such as a lens, etc., a high-refractivity high-dispersion glass is of high utility and occupies an important place. Examples of such a high-refractivity high-dispersion glass include glasses disclosed in Patent Documents 1 to 3. These glasses contain a large amount of Bi2O3 for attaining high-refractivity high-dispersion properties.    [Patent Document 1] JP2002-201039A    [Patent Document 2] JP2006-327926A    [Patent Document 3] JP2007-70156A